Ag Alloy Sputtering Target for Ion Migration Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Miniaturization of electrode and wiring patterns in displays, LEDs, and touch panels leads to increased susceptibility to short-circuiting due to ion migration, necessitating a Ag alloy film with improved environmental and ion migration resistance.
Innovation Solution
A Ag alloy sputtering target with a composition including Cu, Sn, Sb, Mg, In, and Ti in specific atomic percentage ranges, along with sulfur to form silver sulfide, enhancing film wettability and ion migration resistance, while controlling impurity levels to prevent agglomeration and abnormal electrical discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Ag film is used for conductive patterns, then electrical conductivity is improved, but ion migration resistance deteriorates leading to short-circuiting in miniaturized patterns
Solution Approach 1:
The patent uses composite materials by combining Ag with alloying elements (Cu, Sn, Sb, Mg, In, Ti) to create an Ag alloy film that maintains electrical conductivity while improving ion migration resistance. The composite structure prevents Ag ion migration through the alloying elements that form barriers to ion movement.
Solution Approach 2:
The patent changes the compositional parameters of the Ag film by controlling the content of alloying elements within specific ranges (e.g., Cu: 0.1-10.0 at%, Sn: 0.1-5.0 at%, Sb: 0.1-2.0 at%). These parameter changes optimize both electrical conductivity and ion migration resistance without causing short-circuiting.
2Reliability
If alloying elements are added to improve ion migration resistance, then reliability is improved, but film wettability and agglomeration control become problematic
Solution Approach 1:
The patent precisely controls the compositional parameters of multiple alloying elements simultaneously (Cu: 0.1-10.0 at%, Sn: 0.1-5.0 at%, Sb: 0.1-2.0 at%, Mg: 0.1-1.0 at%, In: 0.1-0.5 at%, Ti: 0.1-0.5 at%) to achieve optimal balance between ion migration resistance and film wettability. This multi-parameter optimization prevents agglomeration while maintaining reliability.
Solution Approach 2:
The patent creates a multi-element composite alloy system where different elements work synergistically: Cu and Sn improve wettability, while Sb, Mg, In, and Ti contribute to ion migration resistance. The composite nature of the alloy allows simultaneous optimization of multiple properties that would be conflicting in single-element additions.
3Reliability
If S is added to form silver sulfide for improving ion migration resistance, then reliability is improved, but manufacturing precision becomes challenging due to impurity control
Solution Approach 1:
The patent changes the sulfur content parameter to a very specific range (0.5-200 atppm) to form sufficient silver sulfide for ion migration resistance while maintaining manufacturing precision. This precise parameter control allows the formation of protective sulfide layers without excessive impurity accumulation that would degrade film quality.
Solution Approach 2:
The patent applies local quality by concentrating sulfur at the film surface to form silver sulfide layers where they are most effective for preventing ion migration. The sulfur is not uniformly distributed throughout the bulk but is localized at the surface interface, maximizing its protective effect while minimizing overall impurity content and maintaining manufacturing precision.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The Ag alloy film exhibits excellent heat-moisture resistance and ion migration resistance, effectively preventing short-circuiting in miniaturized patterns and maintaining high electrical conductivity.
Implementation Method 1
a Ag alloy sputtering target... used during depositing a Ag alloy film
Implementation Method 2
since the Ag alloy sputtering target of the present invention includes S in a range of 0.5 atomic ppm or more and 200 atomic ppm or less, silver sulfide is formed on the surface of the deposited Ag alloy film
Data Source
AI summary
A sputtering target, which has a composition comprising: one or more elements selected from Cu, Sn, Sb, Mg, In, and Ti in a range of 0.1 atomic % or more and 15.0 atomic % or less in total; S in a range of 0.5 atomic ppm or more and 200 atomic ppm or less; and a Ag balance including inevitable impurities, is provided.